The invention relates generally to cryosurgery and more particularly to an automated and integrated system including a cryosurgery device, an imaging probe and a computer system for use in performing internal surgery. The attending physician provides input either directly or through the computer while watching a displayed image generated by the imaging probe onto a screen in "real-time." The real-time image will display the extent of tissue freezing with special attention to the border and limits of the desired tissue to be frozen. The physician may directly control, or have the computer system control the duration and the intensity of freezing with passible linkage to shutting of the process if certain predetermined criteria are not met.
The use of cryosurgery dates back to 1964 when Geonder et al. published "Experimental Prostatic Cryosurgery" in Investigative Urology 1:610-619. There is vast clinical accumulation of data on cryosurgery for cancer of the prostate as published by Dr. Loening from Iowa Medical School in the "UROLOGICAL CLINICS OF NORTH AMERICA" 1988.
A key advantage of cryosurgery is that it creates some immune response. Tissue destroyed by cryosurgery can typically be removed from the interior of the body by normal bodily processes. The freezing can be applied by established endo-techniques, such as those utilized in endo-urology, thus avoiding open surgery and enabling tissue destruction in areas where there is no easy access, or where opening of the skin and tissues is not desired.
Current research indicates a scientific interest in combining cryosurgery and ultrasound, in particular on the prostate gland. Onik G., et al, Urology 1991 Mar; 37 (3): 277-81 describe percutaneous transperineal prostate cryosurgery using trans-rectal ultrasound guidance.
Frozen tissue gives a distinct and typical ultrasonic signature. The distinct ultrasonic signature affords the ability to have a computer controlled check-and-balance of the procedure. Onik G., et al., Ultrasound Characteristics of Frozen Prostate, Radiology 1988, Sept: 168 (3): 629-31.
Magnetic resonance imaging (MRI) is a tissue imaging modality that utilizes computers to process magnetic signals and generate images. Castro D. J., MRI guided Nd:YAG interstitial laser Phototherapy (ILP) in an Ex-vivo Model: Dosimetry of Laser Tissue Interactions, Lasers in Surgery and Medicine Supplement, 3:6 1991.
A need has been felt for an apparatus and method for utilizing cryosurgery in a non-open surgical procedure that would permit precise definition of the region of tissue to be destroyed and in addition provide regional tissue definition by real time ultrasound picture or MRI.